Fuel injection pump



Aug."7, 1945. QGAMBR LL 2,381,585 I Y FUEL INJECTION PUMP v Filed Feb. 13, 1945 z Sheets-Sheet 1 to'od'ifierent amountsu 'u4wi d rl ndy cms i 11 v 7. plate tofleiijust the plung'ers in r ders and thereby vary the positions ottheplunG- era with." respect to varying the'charges ofiuel drawn into the respectiye cylinders and the, proportionate part thereof discharged thro Patented Q45 i Application Februery Thisuinyentipn relates to an improvement in 'f i fuel' injection pumps designed primarily lior supzfflplymg; liquidfuel' in; rnetered quantities and at timed intervals to an engine, such as a, Diesel j engine the p ump being.designedfor'fsupplying Iuel'to the cylindersio'f fa multiple cylinderengine jorf k -l -1 I v Many ditl'erenttypes and constructions of fuel injection pumps have been proposed heretofore,

- but most of'thesefhavelbeenimpractical because Of lack insufiicient adjustment to accom mod'ate them to theyarious conditions of opergtion or the engine supplied thereby, or they-have beenf so complex that the construction and use thereot would be impractical.

. n The object of this invention is tosimplify'and' improve the cons'truction of a 'pump'bf; this char- ,acte\' not onlyuto reduce the I herein numloer of struc tural, arts'thereof for practical use, but also toprovide simple'and efiective manner for the accordance with this invention;

- upon operationj' 'of ft invention in the accompanying";

e e" plunge'rsFBy thus adjusting the 'plunger'operating means bodily, allot the vpump plungersare adjusted simultaneously and .to the same extent thereby maintaining the timed relation therebetween and providing for uniform charges to, be illschargedfrom the respectivecylinder's.

. I have showna prefe rrd embodiment of the drawings, in

ioiwhi 1 c.

t Fig; 1 is a sideeleyation of 'a pump; made in "*[Figl- 2 is" enlarged vfertical 'section therethrough, partly in elevation;

ment of thequantity of fuel or '1iq-" vto, ,a plurality'ofcylindersgprovision is'made in j i I 'this'invention tor-uniformly and simultaneously eech"of tlieupump plungrs so they willfsii ply uniform measured quantities even when eiijusted m'the preierred embodimentof the invention,

a the pumpflis constructed of a housing that is jedaptdfto' be mounted stationary with the-ien- 'fgine'thatj is; to besupplied thereby having'cylinders, uniformly spaced f'fromeachother, as around a common axis-;";which cylinders have 'fuel inlet ports and fuel ut1et'or discharge openings,-

' 1 and heve' plungers operatinginsaidfcylinders,

, Provifsion'is'imade forbperating'the' pump plung- 1 ;oersyin timed relation with the engine'and' with each othergas byme'a'1 is' of,-a cam.

" 1n; importa t feature yof this 'inventionzis in themsemmy nnd relationof these-partsitogether rs and fftheir "operating means,

inyention by raisingend lowering the rotary cam the pump cylinthe fuel inlet ports, thereby n the respectiye min r ports from the cylinder.

Fig. 3 horizdntallsectional view" therethe line 3-: ding. 2; t I Fig.4 is

'yiew ion theTline 5- 5 of 'I',h e pumii 'jcbnshi cte ofa housing fdes igpreferably .icupsl'i'aped, and which parts are v p arrangedeinvertical alignmentfwithj each other withntheir me e tingfledges abutting, -,ably connected, as ,by I v o 4, having screw-threaded connection with the part r and detach- 'me ans. of a clamping ring w, 3, and bearingupon e shoulder on the. part 2. The detachable connection of the upper and lower parts 2 and. ;3 ofthehousing .is located adjacent the ,middle ofthe housing to facilitate the construction and assembly otthe parts. Thelower endof, the'housing ;I has a flangedseat 5Qf ormed thereon"'fonmountingthe pump on an engine or 1 other, stationary supportr The upper housing member is constructed owiths'afuel intakeohamber 6 in;theupper end i portion-thereof; which chamber has an inlet pipe I 1 connected therewith to admit liquid into the -=;-'.intakechamber, .as will be evident from Fig. 3.

,2 has: a plurality of: pumpgcylindersj mounted 1 through the intake chem- .I'heclosed endj'of the upper housing member 8 ,arespaced 0n diilferent cylinders may beiused, accordcylinders of the engine to two. of these cylinders are ing to the number of be supplied-thereby,

- shown in the pump illustrated; Each of the cyl- V inders 8 is rigidly mounted in the end wall, structure of'the housing memer 2, clamping "said; end

fa; 'similar'view' on'the' line la- 4 of Riel/5 isvia a" de elevation-of the cam 'platede- .4 7. v 'taehed. where-the pumpis so connected asto supply liquid ered. The upper end of the pump chamber II has a discharge opening, shown as provided with a threaded outlet connection I3 and a checkvalve I in therein to permit discharge" therethrough of the liquid from the pump, and said check-valve prevents the drawing in of the liquid upon the back stroke of the pump, V,

A plunger I4 is mounted in the pump chamber II of each cylinder to reciprocate therein. The outer end of the plungerILhas a capplate. I5 connected therewith against which bears a coiled spring I6, as shown in Fig. 2. The spring I6 is interposed between the cap plate I5 and a seat in a shelf plate I1 mounted within the housing I. The shelf plate I 1 is shown as a flange on a sleeve I! which extends into a recess inja tappet guide block Il. Theshelfplate I1 and the sleeve I8 are secured to the .block. I9 by. a stud bolt 20,

which extends through the sleeve and is screw- -threadedinto the block. The bolt maybe inserted througha .thimble 2| in the closed end of the top housing member 2, which opening is normally closed by1a snap-on cap 22. This opening through the thimble serves also as a breather for the pump mechanismas well as an opening for lubricating the internal parts of the pump.

. The head at the outer end of each pump plunger I4 bears upon a ,tappet 23,?jslidab1y mounted in an orifice .24 in the. guide block Is], whichtappet 1 23 has a roller 25 in position tdbear upon the upperface of a cam plate 21 and :to bear upon the cam 20' which isformed on the upper face of the cam plate 21 when the the rotary movement of the cam plate in the operation of the pump brings'the' cam 26 under the roller.

j j'rne cam plate zines a dependingsleeve 2a therefrom, and is rotatablvmounted;uponanti friction bearings 28 withinJa carriage block 30.

The cam plate 21 has a hub membersecured to the upper'side thereof with a reduced portion 42 journalled in a bearing 38 in the carriage block IS. The block. 30 has its upper edge surround ing the cam plate 21, andhas the tappet guide block I9 'seatedthereon. The blocks I9 and 30 are mounted in thehousing I'for vertical adjustment relativethereto, but'are held against turningmovement therein by keys 3I-(Fig. 5) in opposite sides of the housing, in the form shown.

To provide for such vertical "adjustment, I have shown a cam structure to move the" carriage as-- sembly relative to the housing, whichcam. structure may be formed; according to this embodiment ofthe invention,'by mea'ns of 1 a coarse internal thread 32, withinthe. lower end portion of the block 30, and which thread 32 receives aacoarse cam thread 33 of a rotary member 34. The

I which sleeve is journaled a drive shaft 31. The sleeve is rigidly mounted in the bottom end wall ing and. the shaft 31. The enlarged top end 39. that is splined abuts against the upper end of the sleeve 44, and a drive pinion that would be secured to the lower end of the shaft for connecting the pump with the driving means, would abut against the lowerend of the sleeve 44, whereby the drive shaft would be rotatably mounted in the sleeve 44 but would be held against axial movement therein. Also, this sleeve 44 rigidly mounted in the bottom of the housing, servesas a spindle rotatably mounting the: rotary member 34 thereon, said rotarymember beingheld against axial movement by reason of abutting against a shoulder 41 at the upper end of the sleeve, and having h the flange 43 seated in the end wall structure of the housing, as described above. J'I'he hub portion of the rotary member 34'projects downward, having the gear teeth 35 which engage the teeth of the. transversejadjusting rack 36, whereby transverse adjustment of the rack 36 rotates the rotary member 34 about the axis of said rotary member, which is likewisethefaxis of the sleeve 40 and the shaft 31.

It will be. evident from this structure that the Y blocks I9 and 30 and their connected parts constitute an adjustable carriage assembly that may be movedvertically within and relative to the housing, including the 'actuatingcam and the pump plungers asv well as the springs acting thereon. The blocks I9 'and'30 may be secured together as by boltsor screws 40 (Fig. 5) With the plunger spring shelf plate .I1 also secured I to the block I9, it is evident that these parts will be adjusted in either direction .by anadjustment of the block 30, while being held'against turning movement relative to the housing by the keys 3|.

This forms an adjustable platform upon which the actuating cam plate 21 operates, which cam plate is adjusted with the pump plungers I4 by means of which all of the pump plungers are adjusted simultaneously and to the same extent with respect to the fixed inlet ports I2 in the pump. cylinders. Such an adjustment of this carriage assembly effects anadjustment of the stroke of the pump plungers withfrespect to these I ..fuel inlet ports to varythe amount of the disrotary member 34 is provided with a toothed peripheraliportion 35, meshingwith teeth; on a rack member 36 adaptedto be adjusted lengthwise transversely throughthe housing to rotate the membe'r 34 and adjust thereby the'vertical positions of the blocks I9 and 301m and relative charge through the. respective outlet ports of the pump cylinders. v v

f In operation, fuelissuppliedthrough a suitable connection designated generallyat 1, to the .fuel inlet chamberiiin the top of the housing. The inlet ports I2 are controlled by the respective plungers I4, and when uncovered,- as shown at the left in Fig. 2, fuelis admitted from chamber '6ito the pump chamber 'II on the down stroke of the plunger. The pump plungers I4 are reciprocated by the tappets 2 3 actuated bythe cam 26 on the plate 21, against the tension of the return springs I6. The cam plate 21 is rotated by the driv shaft 31 connected with the engine or other source of power. Upon rotation of the cainplate 21, the cam 26 will press on the roller 25 of the tappet23, moving the latter upward,

portioniof: the fluid in :the

moved newer I I rejected or forced' back om :tl'i'at 'point 'onfithe plunger displaces-the fluid from 'thecylinderin its upward movement, Da Stf-fh'ef check=valve il iia to sthe "injection zline lea'din'g to the engine cylinder other point of -It"wi11 be evident was" tata'y'mu taat is -injected upon each plunger stroke will depend upon the' distaticeo'f travel; of the rplungenabove th'e ginlet' port' during.Pthesworking istroke of. the Z-pluriger. 1 Although -the i-plunger trayelsr 'through e the s'amedistanceiom'eachstroke, its initial :position' relative to lthe'yinleti portzzw'ill Edetermine: the ng-th :o'tsits travel-,ipastzathe,inlet': port upon. its

pwardim ovement inthexpump chamber, and thus r sfan'fiadjustmentxofz {the pumpf plunger relative to the cylinder will vary t he length -.of:'.-its:vtravel igp ttthe -.intake port, thereby; varying the ,quan- I extreme'qpositi'onz of: adj ustm'ent,': the (upper;- edge;

ofztheizp'ump plun'gerswouldfnotfcompletelyl close ltherinlet-port:uporrrrea'chingij-itszupper limit Jo travel;- iandrthereawould be: nc'inje'ction 1 of the port to-a? pointvaboventhe port :formaximummount; of injection. r

onnection :3 S-Jbeo tween/the drivesshajft ;;2f|,-;-'and;the- .cam,-sleeve; "28 provides for aslight circumferentialfadjustport; 1-2 T'untilxthe end iota-the pl'unger passes over'and'eloses off the inlet port;

hus"lifting the.plunger" ll vvhlchis held lnc'on-i a I I I ..'.,be1'-,,of cylindersornother devices to which the tiers I provided ,-shouldlcorresponduwlth the num- -liquid {is to bev supplied under pressure, I although I vmaintaining a L In a liquidrinjectionlpump, the combination ofv a housing, a cylinder mounted inv said housing v and having"intake; and discharge openings, a

.Jtheaout1etsfroin the severalpump cylinders can lie-connected together asa common outlet, if de sired,- in which event the cam structure could be simplifiedsince there would be no necessity for tlmedh lation ofjthe outlet I Iclaimplungen operatively mounted i the I cylinder and .having an edge in position to control.- the intake opening to-trap aquantity of liquidin; the cylingdenand toj discharge the same therefrom, aicam I having operative bearing relation with thetplunger,resilientlmeansacting on the plunger'in opposition to the ;carn,- a-;bejaring ,blocksupporting .said cam and, ;havin ;;means forv journaling the same in the, qhousing, -;me ans; for operating said I cam, means for; adjustingthebearingblock relative to the housing towaryzthe operating position of the plunger relative to .thecylinder,and neans l for adjustingltheresilient means bodi1yl upon ad+ .justmentzof thelbearingfiblock to maintain uni form tension thereof on thesplunge'r in different r adjustedpositionsoftthe cam.

v ;2.-;,In; a:liquid injection pump; the combination of; a: housing, a cylinder mounted in said; nous- :1 :ing and having I intake I and, discharge openings,

mBrifiIiOfi-lhfi tcamyplateidurin vertical adjustf amount of injection, the cam plate 26 is adjusted forwardslightly, so that the lobe ofithe cam passes under the tappet roller 25, earlier in the cycle, thereby" providing automatically for an adjustment of the timing simultaneously with and in proportion to the adjustmentof the quantity of injection.

The carriage assembly is so constructed as to permit of ready assembly and disassembly of the 'a plunger :operatively mounted inflthe; cylinder and having, an edge in position. .to ;,contr'o1 the intake openingtotrapa quantity of liquid i f -thecylinder and to discharge 7 the same therefrom,

a: cam. having; 2 "operative, bearing,- relation with the plunger, resilient meansyacting' on ,the plung- I er in opposition tothe cam; a-bearing blockzs upporting said cam within the housing and having means iournaling the cam for operative move ment, adrive shaft connecting with the cam, cam I means connected with the bearing block for ads justing said bearing'block relative to the hous in toivary the operatingposition of the plunger relative to thecylinder, and means foradjusting the resilient means'bodily uponadjustment Parts of the pump, as well as the adjustment de-Q II scribed. The shelf plate IT is of skeleton shape, or perforatecLto receive readily therein theprojecting end portions of .thepump cylinders 8. In

assembling this mechanism, the plungers l4 and their'return springs I6 may 'be asser'nbled in proper positions relative to'the cylinders 8, and when the two housing sections are joined together, the shelf plate I! can be, anchored then to the adjustable carriage assembly by'inserting the stud bolt 20 through the opening in the thimble 2| and securing it in place. The parts .will then be ready for operation; a I

Although I have shown the cam structure for adjustment of the carriage assembly as formed somewhat resembling acoarsc screw-thread, it

will be evident that various modifications of this adjusting means may bemade within this invention, which willaccommodate theadjustment of 1 thep arts as described, by raising and lowering v the carriage assembly relative to the housing.

' "Although the invention is described primarily .as afuel injection pump, it is evident that it may L be usedwherever desired to obtain a variable;

discharge of liquid under pump pressure, and is 60 supporting said'cam in the housing and journal-- of the bearing blockto maintain uniform tension thereof on the plunger, in difierent adjusted 'positions of the cam.

(3. In a liquidiniectionpump, 'thecoiii'bination; of a housing, a cylinder mounted in said housingand having intake and discharge openings", at

- plungeroperatively mounted in the cylinder and having an edge in position to control the intake openingv to trap va quantity of liquid in the cylining saidjblock for turning movement therein, a drive shaft havingva'slidable splined connection with the cam plate, resilient means bearing against the plunger in a direction opposite to the direction of the cam, means fixed to the bearing block for confining said resilient means, .and

' means for adjusting said bearing block bodily not. limited to the pumping of fuel for internal I combustion engines. The number of pump cy1in-' relative tothehousing to vary the operating position of the plunger relative to the cylinder, said confining means being adjustable with'the bearing'block to maintain uniform. tension on the. l plunger in difierent adjusted positions or the cam m ans.

a housing having a plurality of ,cy1inders'-there a fuel injectionpumm the combinationof, I

in each cylinder andhaving means totrap a quantity of fuel in the cylinder'a'nd to discharge the position to the cam, and means fixed to the bearing blockfor confiningsaid resilientmeans,

5; In a liquid'injection pump, the'combination of a cylinder having intake'and discharge'open- Kings, apiunger operatively mounted; in'the cylinder and having an edge "in position to control "the intake opening, meansfor operating; said plunger'totrap a quantity "of liquid in thecylinder andto discharge-the sametherefrom, means i bearing onsaid plunger and operating saidplungv er relative to the cylinder, means for bodily adjusting saidoperating means relative to the cyl- "inder to vary the operating position of the-piston with respect to the intake port in the cylinder, resilient meansbearing againstthe'plunger in op-.

position to the plunger operating meanspand means fixed'to the adiusting meansforconfining said resilient'means. i

6. In a fuel injection pump, the combination of acylinder having intake and discharge openings, aplunger'-operatively mounted in said cylinde'r and; constructed to trapaquantity of fuel in the'c'ylinder and to discharge the same'therefrom, operating means bearing against the plunger, resilient means bearing against the plunger in "in, each of said cylinders having intake and dis- [charge openings, a plunger operatively mounted v "7. In a fuel injection pump, the combination ofacylinder having intakeand discharge openings, a plunger operatively mounted in said cylinder and constructed tov trap a quantity of fuel inthe cylinder: and to discharge the same thereirom, operating means bearing against the plunger, resilient means bearing against the plunger ient means.

8. In a fuel injectionpummthe combination of means-Iorming a pump c amber having intake erating said, plunger, resilient means bearing against said plungerv in opposition to the operat- 1 ing means, means confiningqsaid resilient means,

and means for adjusting said confining means 'whereby'theplungerxis adjusted relative to the pump chamber.

tive to the cylinder.

I '9. In a liquid injection the combination of a housing, .a cylinder mounted in said housing and "having intake. and. discharge openings, a

plunger operatively mountedin the cylinder and having an edge inpositionto control the intake openin'g'to trap a quantity or liquid in the cylinder and to discharge the same therefrom, a cam having operative bearing relation with the plunger, resilient means acting ;on the plunger in opposition to the cam,v a bearing block having means for confining the resilient means, and

' means for adjusting the position of the bearing block and said cmflning means therewith relamNEsT c. GAMBRELL. 

